The Influence of Slag on the Properties of Fly Ash-based Geopolymer Composites

Inorganic molecules undergo a chemical reaction that results in the production of a brand-new building material known as geopolymer concrete. Otherwise known as an inorganic alumino- hydroxide polymer, geopolymer is made mostly from by-products like fly ash and geologically derived silicon (Si) and aluminium (Al). It is a superior building material for the future because of its great mechanical qualities, significant chemical resistance (attack by magnesium or sulphate), low shrinkage and creep, and environmentally benign nature. It has been proven that geopolymer concrete (GC) is suitable for use in construction projects, including the building of walkways, prefabricated elements, and pavements. The current study intends to construct a road network using GC while sustainably utilizing industrial by-products. GC is a creative and environmentally sustainable alternative to conventional Portland cement (OPC) concrete. In this study, the GC was produced using binders such as fly ash, ground granulated blast furnace slag, and cement. Two distinct types of solutions were required in order to activate these binders (an alkaline solution which was prepared in the laboratory and activator solution purchased commercially). The surface of the GC got denser, which decreased the permeability of chloride ions, water absorption, open porosity, and sorptivity values. The microstructural examination revealed distinct quartz, calcite, and C-A-S-H formations. The 0.45 S/B ratio mixes also showed greater Si/Al ratios and higher quartz and calcite percentages.

Keywords: Geopolymer composites, mechanical properties, microstructural properties, denser structure and durability